Bark

Eucalypts have a very wide variety of bark colour.  The colour will change through the growing season.  As the tree grows in diameter the outer bark stretches and finally cracks. A new periderm is then formed further in and the tissue outside this dies and dries out. On the smooth barked Eucalypts in the early stages of growth the young bark keeps pace with the increasing stem size by radial cell division.

Later the cells cannot keep pace with the internal division and splitting or peeling occurs. Some trees shed this in patches others shed it in long strips during hot weather. This process continues throughout the growing season until the old bark has been shed.

As this happens the older bark changes in colour and the new bark is revealed as a completely contrasting colour.  This contrast is often particularly beautiful. This is not usually seen for the first 2 years, thereafter it is most noticeable in July/August/September.

For species with the most ornamental and interesting bark, see Ornamental bark in the Our Plants section.